Les cyclones tropicaux et le changement climatique

• Published in: Comptes Rendus Geoscience
• Main Authors: J.C., André, Royer, J.F., Chauvin, F.
• Other Authors: Centre Européen de Recherche et de Formation Avancée en Calcul Scientifique (CERFACS), CERFACS, Groupe d'étude de l'atmosphère météorologique (CNRM-GAME), Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: French
• Published: HAL CCSD 2008
• Subjects: Cyclone tropicaux; Activité cyclonique; Observation satellitaire; Changement climatique; Modélisation Tropical cyclones; Cyclonic activity; Satellite observation; Climate change; Modelling; [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]; [SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology; [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; North Atlantic
• Online Access: https://hal-meteofrance.archives-ouvertes.fr/meteo-00353616; https://doi.org/10.1016/j.crte.2008.07.003

Results from observations and modelling studies, a number of which having been used to support the conclusions of the IPCC fourth assessment report, are presented. For the past and present-day (since 1970) periods, the increase of strong cyclonic activity over the North Atlantic Ocean appears to be in good correlation with increasing temperature of the ocean surface. For regions where observational data are of lesser quality, the increasing trend is less clear. In fact, assessing long-term changes is made difficult due to both the multi-decennial natural variability and the lesser coverage of observations before satellites were made available. Indirect observational data, such as those derived from quantitative estimations of damage caused by tropical cyclones, suffer from many artefacts and do not allow the resolving of the issue either. For the future, only numerical three-dimensional climate models can be used. They nevertheless run presently with too-large grid-sizes, so that their results are still not converging. Various simulations lead indeed to different results, and it is very often difficult to find the physical reasons for these differences. One concludes by indicating some ways through which numerical simulations could be improved, leading to a decrease of uncertainties affecting the prediction of cyclonic activity over the next decades. International audience On présente les résultats d'observation et de modélisation, dont nombre ont été utilisés en appui des conclusions du quatrième rapport du GIEC. Pour ce qui concerne la période passée et actuelle, l'activité cyclonique intense a augmenté dans l'Atlantique Nord depuis 1970 environ, en bonne corrélation avec l'augmentation de la température de surface de l'océan. Dans les régions où les données d'observation sont de moindre qualité, la tendance à l'augmentation est moins marquée. De fait, la détection de tendances à long terme est rendue difficile par l'existence d'une variabilité naturelle multidécennale et par la moindre fiabilité des ...